Aeroplane propeller



A. MARTEL, JR. AEROPLANE PROPELLER.

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.m v r WI TNESSES rer OFFEEQ AEROPLANE PROPELLER,

Application filed m 31,

to simultaneously secure a lifting and propelling vaction, and which ismanually controllable to increase or decrease both the lifting andpropelling actions to discontinue the feathering action so that only apropelling force is obtained, and to vary the pitch of the blades toincrease or decrease the propelling action.

I will describe one form of propeller embodying my invention and oneform of aeroplane to which the propeller is applied, and will then pointout the novel features thereof in claims. H

In the accompanying drawings:

Figure l is a view showing in perspective an aeroplane having appliedthereto one form of propeller embodying my invention;

Figure 2 is an enlarged detail view showing in rear elevation the twopropellers shown in Figure 1 and one form of manually operable means foradjusting the propellers also embodying my invention.

Figure 3 is a fragmentary view showing in side elevation and partly insection a portion of the means shown in Figure 2.

Figure l is an enlarged longitudinal sectional view of the hub andadjacent mechanism of either of thepropellers shown in Figure 2.

Figure 5 is a transverse sectional view taken centrally through the hubshown in Figure 4. I m

Figure 6 is a fragmentary perspective view of a portion of thefeathering means shown in Figures 4; and 5. a

Figure 7 is an enlarged vertical sectional view of a portion of themechanism shown in Figure 4.

Similar reference characters refer to similar parts in each of theseveral views.

Referring specifically to the drawlngs and particularly to Figure 1, Ihave in the present instance shown a monoplaneto which Specification ofLettef's Patent. Patnijgfl J 13 1922 i921. Serial No. mm. 7

is applied the propellers embodying my invention, and with theunderstanding that an aeroplane of this type is'shown to simplify thedrawings and to illustrate only one applicatlon-of the propeller. 'Thefuselage of the monoplane is indicated at F, and extend mg from theopposite sides thereof adjacent its forward end are the two sections Sand S- of the main supporting plane. Each section S or S is formed at apoint adjacent the fuselage with a longitudinally extending slot 15 or15 in which is'arranged for rotation in a plane perpendicular to theplane of the main plane, apropellerP or P. The mounting and adjustingmeans for the blades of both propellers is the same so that adescription'of one will suflice for both.

Referring now to Figures 4 and 5, I have here shown a hub designated atH which is mounted for rotation within the slot 15 by means of bearings16 and 16 having flanges 17 and 17 secured to the side walls of the slotby means of bolts 18 and 18 The hub H is made up of two companionsections 19 and 19- which are secured at their edges by means of pins 20and held in hub formation by meansof a sectional casing C, the twosectionsof which are secured to each other by means of bolts 21. Asshown in Figure -fl, the hub H is of substantially ovate formation withthe casing of a corresponding con tour so as to snugly embrace the twosections of the same and thus lock them against displacement. The twosections of the hub are formed at their confronting faces withcooperating depressions to provide a pocket 22 forthe reception of thebearing 16 and other recesses toform a pocket 23 for the reception ofthe cylindrical bearing 16*. The pocket 23 communicates with a pocket 24formed by recessing the confronting sides of the hub sections, andextending into this pocket are shafts 25 and 25 which are journaled inthe sections of the hub in the manner clearly shown in Figure 5, andwhich are rigidly connected to the blades 6 and Z) of the propeller P orP. Ball bearings 26 and 2 are provided between the hub and flanged heads27-and 27 formed on the outer ends of the shafts 25 and 25;respectively, with the heads extending into the blades in the mannershown. These shafts 25 and 25 are disposed in longitudinal alinementwith each other and are connected at their confronting ends by anextension 28 formed on one of the shafts and which threadedly engagesthe Walls of a socket formed in the other shaft,

this connection permitting of the limited in-.

and. to this end I provide a cam K rotatably supported on the free endof a stub-shaft 81 through the medium of ball bearings as shown indotted lines in Figure 4:, with the stub-shaft sustained eccentricallyupon one end of'a main'shaft 32 journaled in the bearing 16*. As shownin Figure 6, the cam K ismade of two sections secured together upon theextension by a screw 76 and a disc 70". The main shaft is provided atits outer end with a gear 33 formed in a recessed portion of the shaftso as to provide at the extreme outerend'an annular flange The gear 33constantly meshes with a pinion 35 fixed to. a tubular shaft 36journaled in a bearing 37 formed'in a plate 38 secured to the flange 117of the bearing 17. Journaled in the shaft 3-6 is a solid shaft 39 whichprojectsbeyond; the shaft 36 at one end where it is. formed with anextension 10 having screw-threaded engagement with the walls of a recess41 formed in the bearing 16 To lock the pinion 35. against longitudinalmovement on the tubular shaft 36, it interposed between the bearing 37and a ring 42 which looselgv embraces the shaft 39 and abuts an annularflange 13 formed on the shaft. The

pinion 35 is 'fOIlllGtl with pins a l adapted toengage in recessesformed in the ring 42 so that the ring rotates with the pinion.

Rotation of the pinion 35 is effected through the medium of a sprocketwheel 45 fixed to the outer end of the shaft 36 and about which istrained a chain 46. Rotation of the pinion obviously effects rotation ofthe shaft 32throu gh the medium of the gear 33:, and: with rotation ofthe main shaft bodily rotation of the cam K is secured. The (am K canalso be shifted laterally in either direction by the longitudinalshifting of the shaft 32. This is effected by rotation of the shaft 39in one direction or the other. When the shaft 59 is rotated in onedirection, the threaded extension effects a longitudinal movement of theshaftgas wil'lbe understood, and with the pinion engaging the gear 33between the main body of the shaft 32 and the flange 34;, it will beclear that the pinion will" engage the main shaft to cause alongitudinal movement thereof in one direction. Conversely, when theshaft 39 rotated in the opposite direction the pinion 35 moved laterallyto effecta movement of or the other to cause circumferential and lateraladjustments of both of the cams K. The means for rotating the shaft 39oomprises sprocket wheels 47, one for each of the shafts 39, and chains18 one for each of the sprockets 17. The chains 48 inaddition to beingtrained about the sprockets 47 are also trained about sprockets 49 and50 fixed to a shaft 51 as clearly shown in'Figure 3. As shown in Figure2 one of the chains 48 is crossed so that the rotation of the corresponding sprocket wheel is in the direction opposite to the direction ofnotation of the other sprocket wheel, all as clearly indicated by thearrows. The shaft 51 is adapted to be rotated in one direction or theother by a sprocket wheel 52 mounted on a shaft 53 and provided with ahandle 54: for manually operating thesame. A sprocket 55 is fixed to,the shaft 51 between the wheels49 and 50, and this sprocket isoperatively connected with the sprocket 52 by a chain 56. The sprocket52 is disposed above the shaft 51 so as to be in convenient position formanipulation by the operator of the aeroplane.

Operation of the tubular shafts 86 is obtained by means of .a wheel 57fixed to a shaft 58, and fixed to this same shaft are sprocket wheels 59one of which is opera-- tively connected to one of the sprocket wheels4-5 by a chain 60, while the otheris operatively connected to the othersprocket wheel 415 by a chain 61. This arrangement causes the rotationofthe. two shafts 36' inthe same direction when the wheel 57 is rotatedby means of a handle 62.

In the operation of the propellers P and P, when within the sections, ofthe main plane as shown in Figure 1, the hubs there of are driven bylarge sprocket wheels 63 operatively connected to the motor throughsuitable mechanism (not shown) and in such manner that the twopropellers rotate in opposite directions. During rotation of eitherpropeller, the arms 29 and 29 rotate about the hub axis as a center atthe same time maintaining engagement with. the cam K. Nith the cam inthe posit-ion shown in Figures l to 6, which is one of its extremepositions, the arms are caused toescillate during rotation therebyeffecting a feathering of the blades Z) and 5.- Because of the contourand eccentric mounting of the cam with respect to the axis of the shaft32, it is capable of occupying'two extreme positions and numerousintermediate positions between the two extreme positions. Theseadjustments are obtained by rotation of the main shaft 32 as has beendescribed. The cam is shown in one extreme position in solid lines andin the other extreme posi tion in dash lines, both in Figures 4 and 5.In one extreme position of the cam its axis is disposed the greatestpossible distance from the axis of the hub-H,,while in the other extremeposition its axis is coincident with the axis of the hub.

By observing the position of the arms 29 and 29 in Figure 4:, it will beclear that with the cam in one extreme position the arms will, duringone complete revolution of the propeller, oscillate through an arc ofsubstantially 90,with one arm moving in an opposite direction to themovement of the other arm. By this operation, the blades 6 and b arecaused to oscillate through the same are and in the same direction,thereby effecting the feathering action. This position is thereforetermed the feathering position of the cam. l/Vhen moving the cam fromthis feathering position toward the other extreme position, the arcsdescribed by the arms are naturally reduced, resulting in a decreasedfeathering action of the blades until finally, when the cam reaches theextreme position, the feathering action is completely discontinued. Thisother extreme position is therefore termed the non-feathering position.In the non feathering position of the'ca m, the blades of the propellerare at intersecting angles of substantially d5", which is the normalposition of propeller blades.

In addition to securing the feathering action of the blades, they arealso capable of being varied in pitch so as to vary the angle of attack.This is accomplished by effecting a lateral shifting of the cam Kthrough a longitudinal shifting of the main shaft 32 in the mannerpreviously described. By a consideration of Figures 4 and 6 and assumingthat the cam K is in neutral position, it will be clear that when thecam is moved to the right the arms will be actuated to increase thepitch of the blades 6 and 6, while when moved to the left the arms willbe moved to decrease the pitch of the blades. It is to be understoodthat the variance in pitch of the blades of the propeller only occurswhen the cam K is in neutral position, or in other words, when the axisof the cam coincides with the axis of the hub, and there is nofeathering action of the blades.

In practice, the two cams of the propellers P and P normally occupy thefeathering position in which the feathering action of the blades is at amaximum, This condition exists when the aeroplane is making a. takeoffor landing, and it is desired to secure a maximum lifting action and aminimum propelling action. After the machine rises from the ground andthe desired altitude is obtained, the cams are gradually moved to anon-feathering position thereby gradually reducing the feathering actionof the blades and consequently reducing the lifting action of thepropellers. With the reduction of the lifting action, it will be clearthat there is a corresponding increase of the propelling action so thatwhen the cams are in nonfeathering position the propelling action is ata. maximum. If it is desired to increase or decrease the propellingaction this-can be obtained by a lateral adjustment of the cam as hasbeen described.

From the foregoing operation taken in conjunction with the accompanyingdraw ings, it will be manifest that I have pro vided simple andefficient mechanism by means of which the blades of a propeller can befeathered to any degree or varied in pitch within the will of theoperator during flight so as to completely control both vertical andhorizontal movements of the aeroplane. It is to'be particularly notedthat because of the connection between the shafts 25-and 25 they arelocked to each other. for rotation in one direction so that during thefeathering action of the blades each blade assists the other.

Although I have herein shown and described" onlyione form of aeroplanepropeller embodying my invention, it is to be understood that variouschanges and modifications may be made herein without departing from thespirit of the invention and the spirit and scope ofthe appended claims.

What I claim is:

1. A propeller comprising a hub mounted for rotation, shafts ournaleclin the hub and extending diametrically of the same, blades carried bysaid shafts, arms fixed to said shafts, means engageable with the armsfor effecting oscillatory movement thereof when the hub is rotated tocause a feathering of the blades, said means being adjustable toincrease or decrease the oscillatory movement of the arms to vary thefeathering action of the blades, and manually operable means foractuating the same.

2. A propeller comprising a hub mounted for rotation, shafts journaledin the hub and extending diametrically of the same, blades carried bysaid shafts, arms fixed to said shafts, means engageable with the armsfor effecting oscillatory movement thereof when the hub is rotated tocause a feathering of the blades, said means being adjustable toincrease the feathering action of the blades and to decrease such actionto a point wherein there is no feathering action of the blades, andmeans for actuating-said first means to vary the pitch of the blades.

3. A propeller comprising a hub mounted for rotation, shafts ournaled inthe hub,

said shafts within thehub, a member engageable with the arms and movableto occupy two extreme positionswhereby when said hub is rotated themember operates the arm to effect a feathering of the blades when' inone extreme position and to discontinue the feathering operation when inthe other extreme position, said member being also capable ofadjustments whereby the arms are caused to occupy various positions toincrease or decrease the normal pitch of the blades, and means foractuating said member.

5. A propeller comprisinga. hub mounted for rotation, shafts journaledin the hub, blades fixed to said shafts, arms fixed to said shaftswithin the hub, and means supported upon the hub and engaging said armsto effect an oscillatory movement thereof when the hub is rotated.

6. A propeller comprising a hub mounted for rotation, shafts ournaled inthe hub and extending diametrically of the same, blades fixed to saidshafts, arms fixed to said shafts, a main shaft mounted in the hub andhaving its axis disalined with the axisof the hub, a cam mountedeccentrically on the main shaft and interposed between said. arms, saidmain shaft being rotatable to effect a circumferential adjustment ofsaid earn and movable longitudinally to effect a lateral adjustment ofsaid cam for the purposes described, and manually operable means foractuating said shaft.

7. A propeller comprising a hub mounted for. rotation, shafts journaledin and arranged diametrically of the hub, blades fixed to said. shafts,curved arms fixed to said shafts, a mainshaft mounted in the hub withits axis disalined with the axis of the hub, a cam sustained on the mainshaft and eccentrically of the hub axis, said cam having a roundedperiphery and engageable with said arms to control the positionsthereof, means for rotating the main shaft to effeet a circumferentialadjustment 'of the cam. and means for shifting said main shaftlongitudinally to effect a lateral adjustment of said cam. v

8; A propeller comprising a hub mounted for rotation, shafts journaledin and arranged diametrically of the hub, blades fixed to said shafts,curved arms fixed to said shafts, a main shaft mounted in the hub withits axis disalined with the axis of the hub, a cam sustained eccen,

trically on the main shaft, said cam having a rounded periphery andengageable with said arms to control the positions thereof, means forrotating the main shaft to effeet a circumferential adjustment of thecam, comprising a gear of a diameter less than the diameter of the shaftfixed to one cud of the shaft, a flange secured to said gear, a pinionmeshingwith said gear. means for rotating said pinion, and means forlaterally shifting said pinion in one direction 9. A propellercomprising a 'sectional hub mounted for rotation, shafts journaled inthe hub and arranged diametrically ofv the same, blades fixed to saidshafts, arcuately curved arms fixed to said shafts, a main shaftjournaled in the hub andhavil ig its axisdis I alined with the axis ofthe hub, an extension. eccentrically positioned on one end of the mainshaft, a'cam rotatably mounted on said extension, said cam having itsperiphery rounded to conform to the curvature of said arms andengageable with said arms for positioning the latter, means for rotatingthe main shaft whereby an adjustment of the cam is effected in the planeof the cam, and means for shifting the main shaft longitudinally toeffect said cam. 3

ll). A propellercomprising a hub formed of sections recessed at-theirconfronting'sides to provide bearing receiving poclrets, and a pocketmedially of the ends of the hub which communicates with" one of thebearing pockets, a pair of shafts journaled diametrically in the hub andextending into the me dial pocket, blades fixed to said shafts, armsfixed to said shafts within said pocket, a bearing in one of thepockets, a main shaft journaled in said, bearing and having the axisthereof disalined with the axis of said hub, an extension eccentricallysustained on the main shaft, a cam carried by said extension andinterposed between saidarms, means for rotating the 'main shaft, andmeans for shifting the main shaft longitudinally in either direction.

11. A propeller comprising ahub mounted'for rotation, shafts extendingdiametrically of the hub and arranged in alinement with each other,means for connecting the confronting ends of said shafts to permit:

dependent or independent rotation of the shafts,blades fixed to saidshafts, arms fixed a lateral adjustment of to said shafts, a cam mountedfor bodily movement in a circle, the axis of which is eccentric withrespect to the axis of the hub said cam also being capable of lateraladjust ment in either direction, all for the purpose described.

12. A propeller comprising a hub mounted for rotation, shafts journalledin the hub blades fixed to said shafts, arms fixed to said shafts withinthe hub, and means sup- 10 ported upon the hub and engaging said arms toeffect an oscillatory movement thereof when the hub is rotated saidmeans being movable relatively to the arms to vary the extent ofoscillatory movement of the 15 latter.

ALFRED MARTEL, JR.

